Note 2. Investments and Restricted Cash (Detail) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 Unrealized Losses [Member]	Sep. 30, 2012 Unrealized Gains [Member]
Long-term Investments	$ 9,023,000	$ 3,923,000
Tax Basis of Investments, Cost for Income Tax Purposes	6,800,000	3,500,000
Payments to Acquire Available-for-sale Securities, Equity	3,300,000
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax			2,900,000	600,000
Restricted Cash and Cash Equivalents, Noncurrent	$ 866,000	$ 866,000